After more than a decade of pressing Congress for funding to build a new campus in the Washington suburbs, the FBI is now proposing that it keep some of its employees exactly where they are — on Pennsylvania Avenue in downtown D.C. — and moving 2,300 out of the Washington area altogether, to Alabama, Idaho and West Virginia.

The proposal is a dramatic about-face from the stance the government took under Presidents George W. Bush and Barack Obama. For years, the General Services Administration, which oversees federal real estate, had insisted to lawmakers and the public that the FBI required a suburban Washington campus where it could consolidate 11,000 FBI personnel in a modern and secure facility.

Instead, on Monday the Trump administration proposed keeping about 8,300 FBI headquarters staff in the Washington area, split between a new headquarters to be built in place of the aging J. Edgar Hoover Building and Quantico, Va., home to the bureau’s training academy.

Assistant Attorney General Lee Lofthus told reporters at a news briefing that $2.175 billion from the administration’s infrastructure budget would be added to FBI funds previously set aside for the project. He said the total $3.3 billion would afford “a modern and secure building” across the street from the Justice Department headquarters but that there is no timeline available yet.

The new money is part of the administration’s infrastructure package but still has to be approved by Congress. “This is an important part of the president’s infrastructure building, and folks are pleased that we can have money for the FBI Building,” Lofthus said.

Despite President Trump’s repeated calls to “drain the swamp,” the decision still stunned FBI experts and members of Congress. The GSA and FBI spent several years, thousands of hours of staff time and millions of dollars securing approvals for sites in Greenbelt and Landover, in the Maryland suburbs, and in Springfield, Va.

Redeveloping the Hoover Building — a block from Trump’s luxury D.C. hotel — would have returned some of the District’s most valuable real estate to its tax base and brought new housing, offices and retail to Pennsylvania Avenue.

Instead, in a 23-page report to the Senate Committee on Environment and Public Works, obtained by The Washington Post, the GSA calls for a “nationally-focused consolidation plan.”

“This sudden and unexpected decision by the Trump Administration raises serious questions about what or who could have motivated such a decision. Why the Trump Administration would so suddenly forgo years of study that led to careful recommendations — not to mention the millions of dollars spent in the effort to move the Bureau’s headquarters — is beyond astounding, and quite frankly, extremely alarming,” Hoyer said in a statement. He called for Congress to reject the plan.

For more than a decade, there has been widespread agreement that the Hoover Building needs to be replaced. Netting hangs on the Ninth Street facade to prevent broken concrete from hitting passersby 160 feet down on the sidewalk below. The building falls well short of many security requirements put in place after the Sept. 11, 2001, attacks.

Within the federal government, some have argued that the FBI should stay where it is to make sure the agency is still in close and constant contact with the Justice Department — because putting more physical distance between the two agencies could give the FBI more leeway than it should have when conducting important investigations, according to people familiar with the discussions.

That argument, however, is based on a particular view of the politics of federal bureaucracy — that moving the FBI out to a suburban area could give elected officials less understanding and control of what it is doing.

Experts said the government’s expectations of cost savings weren’t likely to come true based on unrealistic expectations on the administration’s part about how little its plan will cost.

“It ignores multiple hundred-million-dollar costs in order to inaccurately and shockingly say that building in place is the cheapest option,” said one expert who has studied the project for years but who was not authorized to speak publicly about it. “Five years ago, the GSA rightly said building in place was the most expensive option.”

When the GSA canceled the previous plan, in July, it cited the need for appropriations as the reason. But the new plan calls for seeking $2.2 billion in appropriations. “It completely contradicts their July analysis,” the expert said.

GSA officials issued a statement saying the agency considered “several acquisition strategies” before deciding the best option to rebuild on the site. They did not return requests for further comment.